In chapter 1 we discuss the all important lowest layer of the atmosphere, called the troposphere. In the beginning of chapter 2 we are discussing the basics of weather forecasting….the clouds.

1. Weather2020 Forecast School
Learning Weather Forecasting
From 1 Day to 200 Days Into The Future
By Gary Lezak

2. Introduction
Meteorologist Gary Lezak will introduce us
to meteorology. Gary received his Bachelor
of Science Meteorology degree in 1985
from the University of Oklahoma. He has
been rated one of the most accurate
weather forecasters in the nation and he is
going to be providing some insight into
weather forecasting both short and long
range using the Lezak Recurring Cycle
(LRC). This is breakthrough technology that
is now being used around the world in the
1Weather app and on Weather2020.com.
This introduction into weather forecasting
will begin with an understanding of the
troposphere. We will then take you through
one of the most important and visual parts
of weather forecasting, the clouds, storm
systems, and surface analysis. By the end
of this educational series you should have
enough knowledge to strengthen your
weather forecasting skills.

3. Chapter 1: The Atmosphere
Most of the weight of the atmosphere
is within the troposphere, which is
78% Nitrogen, and 21% Oxygen.
The troposphere begins at the
surface of the earth and extends up
to around 5 to 13 miles depending
on the location and season. During
the winter the troposphere is lower
and it is more expansive during the
warm months. For the same reason
it is much higher at the equator than
it is at the poles.
The temperature in the troposphere
decreases with height due to lower
density of the gasses with height.
The air becomes thinner and the
temperature drops. The top of the
troposphere is called the tropopause.
Did you know that you have visually
experienced the top of troposphere
many times in your life?

4. The cumulonimbus cloud, you can see
here, showcases the entire troposphere.
In the troposphere the temperatures cool
with height. When a cumulus cloud is
growing, water vapor is condensing into
cloud droplets and heat is released in this
condensation process. The heat allows
the air within the rising cloud to be
warmer than the surrounding
environment and the air will continue to
rise and the cloud grows. There is an
upper limit, however, to how high the
cloud can grow. Once the cloud hits the
stratosphere, where the air begins
warming again, the cloud is forced to stop
growing and this can be seen in every
thunderstorm that forms. The anvil
spreads out, the top of the thunderstorm,
and this shows that where the top of the
troposphere is located. So, when it is
raining, we are literally seeing the effects
of the cumulonimbus cloud from the
ground all the way up to the bottom of the
stratosphere.

5. All of the weather we experience here on earth
forms within the troposphere. The other layers of
the atmosphere likely have very little influence on
the turbulent layer that lies near the surface.
What’s incredible is how thin this layer really is.
Remember the troposphere goes up to around 12
to 14 miles at the most. The largest
cumulonimbus clouds have been known to reach
close to 70,000 feet up. So, let’s say the upper
limits of the troposphere is 14 miles. And now,
let’s imagine you driving from Shawnee, KS
across the Kansas/Missouri border to Raytown,
MO, both suburbs of Kansas City. If you were to
draw a straight line that distance would be 14
miles. Now, look at the second map below. Look
how tiny of a distance that is when you think of
the bigger global picture.
99% of the atmosphere’s water vapor is
contained in this area near the earth’s surface,
within the troposphere. And 75% of the weight of
the atmosphere is in this layer.
The next time you look up at the sky, try to think
of the troposphere, and what is happening in this
layer. This is just one of the basic topics that we
need to learn to become a great weather
forecaster.

6. This diagram comes from http://scied.ucar.edu/shortcontent/troposphere-overview. This shows
what is happening within the troposphere and what happens above the tropopause. The Ozone
layer is up in the stratosphere, and the amount of solar radiation that reaches the surface of the
earth is affected, but the weather we experience on earth is driven by what happens within the
lowest layer, the troposphere. The process of developing clouds and precipitation can be quite
violent and we will be discussing this turbulence in the cloud series.

7. Clouds are the basics
of weather forecasting.
Getting a good
understanding of the
cloud types, being able
to identify them in the
sky, and understand at
least a little bit in how
they form will help you
become a better
weather forecaster.
In this chapter we will
go over the process of
how clouds form and
we will begin testing
our skills by just
looking up at the sky.
The cloud chart here
shows all of the basic
cloud types and the
levels that you are
most likely to
experience these.
Chapter 2: Clouds

8. As we discussed in chapter 1 99% of
the water vapor in the atmosphere is
contained within the troposphere.
The process of cloud development
begins with by looking at the water
cycle here on Earth.
In this diagram you can see the full
water cycle. It begins with
evaporation. Water evaporates from
the large water areas around our
world. The water vapor that is added
to the air just needs a lifting
mechanism, something to create
rising air, and then water vapor can
condense into clouds. This is the
next process, condensation. Then,
incredibly, the clouds can build with
precipitation forming and then being
released back down to the ground
and the water cycle is then
completed by the runoff of the rain
and melted snow back into the
ground and bodies of water.

9. For a cloud to develop there is one essential ingredient that must be in the air. Extremely small
particles called condensation nuclei must be in the air for water vapor to condense. If the air is
perfectly clean then there would be no clouds. Condensation nuclei come in the form of salt
particles from the oceans, dust particles, and other very small airborne particles that are too small
to see. The main ways in which these get in the air are from ocean sprays, fires, dust storms, and
other ways that we pollute the air as humans. In this diagram below you can see the complex
process of forming a raindrop beginning with the nucleus of a very small airborne particle. These
particles are called hygroscopic (“water seeking”) with an extremely light massof less than one-
trillionth of a gram. Sea salt and table salt are hygroscopic. When it is extremely humid, salt from
a salt shaker can become difficult to pour due to water vapor condensing onto the salt.
Sometimes you can see these small particles before condensation occurs when there is an
abundance of them in the air. This is visible when it seems hazy outside. So, what is a cloud. Yes,
it begins with the condensation nuclei, but clouds are really visible when condensation occurs and
billions of these small particles come together to form into clouds. Clouds are the basics of
weather forecasting and we will begin a look into the cloud types in the next section.

10. There are ten basic cloud types and we will begin this discussion next week.
Cloud Types